Is there a live or private communication element to Discourse? More like IRC or chat than forum?
There are personal messages (which can have multiple participants, if required) - or you can set up private categories.
(as suggested in another topic related topic)
or have a look at Babble:
There’s a recent blog post from our very own @erlend_sh that goes into detail here.
TL;DR we integrate tightly with chat, but we aren’t chat. The unit of work in the chat is the word. the unit of work in Discourse is the sentence and ideally the paragraph. Different beats.